Display devices and, in particular, liquid crystal display devices, are used on many occasions as display devices of PCs (Personal Computers) because they are small, lightweight and offer space savings. Due to the diversity of the application programs that are run on PCs, there are instances where it is appropriate to use the long side of the screen vertically and parallel to the upright direction rather than using the screen, which has a substantially rectangular shape, horizontally. For example, when content on the Internet is viewed by means of a browser, because displaying the browser on a vertical screen reduces the need for vertical screen scrolling on account of the large amount of information displayed at the same time, such a display is easy for the user to use. In addition, so too with document editing, when a vertical document screen is displayed in full screen mode, the vertical screen is easy to see and easy to edit. Accordingly, cases where users employ display devices by frequently changing the vertical or horizontal orientation of the screen in accordance with the application program are also increasing.
Various proposals have been made in the prior art with respect to display devices that allow the orientation of such a screen to be changed. According to Japanese Application Laid Open No. H11-338363, a thin-type display device and a screen vertical and horizontal switching mechanism that simplifies the structure by integrating the rotation mechanism required to change the orientation of the screen and the vertical movement mechanism that adjusts the height of the screen rather than separating these two mechanisms have been proposed. Furthermore, according to Japanese Application Laid Open No. H11-7250, a thin-type display device that allows interference with the floor of the screen when switching between a vertical and horizontal orientation to be prevented and allows the screen position when the screen has an upright orientation to be lowered has been proposed. In addition, according to Japanese Application Laid Open No. H10-240140, a thin-type display device in which the rotational center is designed so that the screen center in the vertical position and the screen center in the horizontal position are different has been proposed. Furthermore, according to Japanese Application Laid Open No. 2000-47591, a display device that comprises an open/close mechanism that moves to open and close a shutter in accordance with the rotation of the display section and in which an air-hole shutter located at the top of the display section is open irrespective of the vertical or horizontal orientation of the display section has been proposed.
However, in the prior art, which relates to a display device that allows the orientation of the screen to be changed, the rotational center does not necessarily match the screen center, the rotation operation lacks balance, and weight is placed on inclined parts. Therefore, wear damage to members which are used as the rotation mechanism and the support mechanism for supporting the screen is sometimes premature. When members wear out due to periods of long usage, in cases where the user removes the hand supporting the rotation operation by mistake, the display device is damaged through contact with the floor or desk as a result of the screen turning by itself due to the eccentricity of the rotational center and the possibility exists that the user will be injured.
Furthermore, in the prior art, there have been instances where the direction of rotation is one preset direction and, when the user applies an excessive force by mistake in the direction in which the screen is unable to rotate, the result has been damage to the rotational mechanism. Thus, the mismatch between the rotational center and screen center and the asymmetry such that rotation is possible in only one direction are not user-friendly and bring about the result of reducing the user convenience of the product.
In addition, when accessories such as operation keys for making adjustments to the speaker or screen are provided on the display device, the accessories have sometimes been moved to positions in which the accessories rotate together with the rotation of the screen and are used when the screen has a vertical or horizontal orientation. Although there are also products that allow accessories to be detached from the screen, there is work required in re-attaching the accessories at suitable points after the orientation of the screen is changed, which is troublesome.